Water-reducing additives for concretes are high efficiency dispersants that promote reduction of viscosity in suspensions, minimizing the amount of water used to hydrate the cement, thus enabling the fabrication of concrete with excellent properties. However, different forms of interaction between cement and additives are observed. In this work the properties of concrete formulated with three dosages of a polycarboxylate-based water-reducing additive and cement type CPII E-32 from two distinct manufacturers were investigated. In the experimental part, we verified the importance to use this technology justified by excellent results obtained for mechanical resistance and plasticity properties of the concretes. Through statistical analysis it was possible to point a discrete superiority in compositions using Holcim cement in function of its physical and chemical characteristics, in which the interaction process showed to be more efficient.
The curing process is one of the main steps after concrete molding, playing a direct role in maintenance of ideal conditions related to temperature decrease of exothermal reactions and severe environmental conditions, thus avoiding possible losses of water mass from the material to the environment. Overall the curing process must act from the initial period of microstructure formation and development, a period in which the material has low resistance properties towards tensions created from high rates of water loss leading to retraction, and micro fissures formation and development. In this work we investigated the influence of different curing processes in mechanical resistance properties of concretes aged 7, 14, 28, and 56 days. It was observed experimentally that the curing process by immersion was more efficient compared to humid and chemical curing processes, with mechanical resistance to compression values of 39.56 MPa (± 2,23), that is, 24% greater. For samples not subjected to the curing process, we observed losses of 29.27% in mechanical resistance to compression. These results highlight the importance of appropriate curing processes in cement-based materials.
Concrete mixing technology has spread with the development of water-reducing additives, enabling production of high quality products. Despite the discoveries and important technological advances, occurrences concerning the incompatibility between sealers and additives have been reported. The main incompatibilities occur between additive and cement of different brands, or different batches. This study investigated the influence of a superplasticizer on the properties of two cements of the same class (type CP II E 32), but different manufacturers. Two cements (without the presence of the additive) were characterized by physical, chemical and mechanical tests. The setting times for pastes made from cement, water and superplasticizer mixtures were determined. The results showed a significant difference in physical, chemical and mechanical properties of cements, as well as those related to the hydration process thereof.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.